In cellular networks, such as a cellular network based on the LTE (Long Term Evolution) radio technology specified by 3GPP (3rd Generation Partnership Project), it is typically required that a frequency utilized by a radio receiver/transmitter in a user equipment (UE) matches a frequency utilized by a radio receiver/transmitter in a base station of the cellular network, in the LTE radio technology referred to as eNB (evolved Node B). To meet this requirement, the UE may perform frequency offset measurements based on reference signals transmitted by the base station. In the LTE radio technology, these frequency measurements are typically performed on cell-specific reference symbols (CRS) which are distributed over a wide frequency band of up to 20 MHz.
One aspect of the LTE radio technology specifically addresses Machine Type Communications (MTC) and a corresponding class of UEs, referred to as MTC device, as well as specific features to support efficient MTC have been defined on both on the network side and the UE side. For example, an MTC device is typically operated in a narrow frequency band of 1.4 MHz. This operation is also referred to as narrowband LTE. In a specific variant referred to as NB-IoT (Narrow Band Internet of Things), the utilized bandwidth can be even as small as 200 kHz.
In view of the operating bandwidth being is smaller than the total bandwidth offered by the eNB, frequency offset measurements based on CRS may be problematic in the case of an MTC device. Specifically, due to the limited bandwidth the MTC device is not able to receive all CRS which are distributed over the entire bandwidth offered by the eNB.
Accordingly, there is a need for techniques that allow for efficiently estimating the frequency offset, specifically by radio devices operated with a limited frequency bandwidth, which is smaller than a total bandwidth utilized by the base station.